1. Field of the Invention
The present invention relates to a flying type thin film magnetic head provided with a thin film magnetic transducing element at an end surface of the slider. More particularly, it relates to a flying type thin film magnetic head wherein the bonding pad of the thin film magnetic transducing element is extended to the surface of the slider which opposes a magnetic medium.
2. Discussion of Background
There has been known, for a magnetic disk drive, a flying type thin film magnetic head which floats with a space by a minute air bearing to a magnetic recording medium by utilizing a dynamic pressure resulted when the magnetic recording medium is moved. Such a flying type thin film magnetic head is disclosed in U.S. Pat. Nos. 4,130,847, 4,218,715 and 4,219,853. Namely, the basic construction of the conventional magnetic head is such that two rail portions are formed with a space therebetween at the surface of the slider made of ceramics which opposes the magnetic recording medium so that the surface between the rail portions functions as an air bearing surface, and a tapered portion is formed at each one end (at the air intake side) of the rail portions so that a lifting force is produced at the tapered portions in association with the magnetic recording medium. The thin film magnetic transducing element is prepared in accordance with the same process as an IC manufacturing technology, and is formed or attached at the air discharging side which opposes the tapered portions of the slider.
In the thin film magnetic head of this kind, there is a trend of miniaturization in order to comply with a demand of high density and high speed magnetic recording. The miniaturization of the thin film magnetic head is effective to reduce a flying height necessary for the high density recording and to reduce a spacing loss. Further, it is advantageous to increase the resonance frequency in association with a gimbal device, to eliminate crushing and to improve durability. In addition, an appropriate balance is obtainable between the dynamic pressure and the pressure of a supporting spring and the posture of the magnetic head can be properly maintained, whereby a stable flying characteristic can be obtained. Further, reduction in the mass of the magnetic head obtained by the miniaturization increases the speed of accessing movement of an arm for supporting the gimbal device.
It is, however, difficult to reduce the size of the conventional flying type thin film magnetic head because it has a complicated structure such that the rail portions and the tapered portions are provided at the surface of the slider opposing the magnetic recording medium. To solve this problem, there has been proposed a thin film magnetic head wherein the surface of the slider opposing the magnetic recording medium is made flat without forming the rail portions (e.g. in U.S. Pat. No. 4,803,577). FIG. 12 is a perspective view of such thin film magnetic head of the above-mentioned type. In FIG. 12, a reference numeral 1 designates a slider, a numeral 2 designates a thin film magnetic transducing element and numerals 3, 4 designate bonding pads. The slider 1 has a medium-opposing surface 101 which is made flat without forming rail portions and tapered surfaces and the opposing surface 101 which functions, as a whole, as an air bearing surface.
The thin film magnetic transducing element 2 is attached to an end surface of the slider 1 which is an end in the direction of air discharging in combination with the magnetic recording medium. The element 2 used is a single which is disposed around an intermediate portion in the width direction of the slider 1.
The bonding pads 3, 4 are connected to both ends of a conductor coil film which constitutes the thin film magnetic transducing element 2.
In a case that the magnetic head is used in a magnetic disk drive, it is driven by a so-called contact.start.stop method wherein the surface 102 opposite the medium-opposing surface 101 is attached to a gimbal type magnetic head supporting device (not shown) while the medium-opposing surface 101 is brought into spring-contact with the surface of the magnetic disk, and starting and stopping are carried out in this state. When the magnetic disk is in a stationary state, the medium-opposing surface 101 is pushed to the surface of the magnetic disk by the spring action of the magnetic head supporting device. However, when the magnetic disk is rotated, a dynamic pressure for floating the slider 1 to the medium-opposing surface 101 is produced, whereby a flying height obtained by balancing the dynamic pressure and the spring pressure of the magnetic head supporting device is provided.
Since the thin film magnetic head as shown in FIG. 12 is provided with the medium-opposing surface 101 in the slider 1 which is simply flat without rail portions, it is possible to reduce the size of the magnetic head to thereby assure the above-mentioned advantage.
However, the above-mentioned thin film magnetic head has the following problems.
(A) Since the thin film magnetic transducing element 2 and the bonding pads 3, 4 are positioned on the same end surface 103, the surface area of the end surface 103 is limited because of the surface area required for positioning the thin film magnetic transducing element 2 and the bonding pads 3, 4, and accordingly, there is a limitation for miniaturizing the thin film magnetic head. PA0 (B) In a thin film magnetic head of this kind, generally, a head supporting device is attached to the surface 102 which is opposite the medium-opposing surface. Lead wires for a reading/writing circuit which are electrically connected to the bonding pads 3, 4 of the thin film magnetic head 2 are supported and guided by the head supporting device. When the lead wires are to be connected to the bonding pads 3, 4, it is necessary to bend the lead wires from the surface 102 to the surface 103 and to connect them to the conductor coil. The connecting operation is troublesome. Further, an excessive external force is produced due to the spring action of the lead wires, which gives bad influence on the floating characteristic of the thin film magnetic head. PA0 (C) The both side end portions in the width direction of the medium-opposing surface 101 project while the intermediate portion recesses due to the deformation of a workpiece during machining operations in order to produce the slider, as illustrated in FIG. 13 with a great exaggeration. When such projections and the recess are produced in the medium-opposing surface 101, a proper contact of the magnetic head to the magnetic disk can not be obtained, whereby good head touch can not be obtained; a spacing loss becomes large and head-crushing may be caused. The durability of the magnetic head is also reduced.